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61.
Miriam YH Ueda Paulo G Alvarenga Juliana M Real Eloisa de Sá Moreira Aripuan? Watanabe Ana Maria Passos-Castilho Matheus Vescovi Yana Novis Vanderson Rocha Adriana Seber Jose SR Oliveira Celso A Rodrigues Celso FH Granato 《Memórias do Instituto Oswaldo Cruz》2015,110(4):461-467
Human herpesvirus 6 (HHV-6) may cause severe complications after haematopoietic stem
cell transplantation (HSCT). Monitoring this virus and providing precise, rapid and
early diagnosis of related clinical diseases, constitute essential measures to
improve outcomes. A prospective survey on the incidence and clinical features of
HHV-6 infections after HSCT has not yet been conducted in Brazilian patients and the
impact of this infection on HSCT outcome remains unclear. A rapid test based on
real-time quantitative polymerase chain reaction (qPCR) has been optimised to screen
and quantify clinical samples for HHV-6. The detection step was based on reaction
with TaqMan® hydrolysis probes. A set of previously described primers and
probes have been tested to evaluate efficiency, sensitivity and reproducibility. The
target efficiency range was 91.4% with linearity ranging from 10-106
copies/reaction and a limit of detection of five copies/reaction or 250 copies/mL of
plasma. The qPCR assay developed in the present study was simple, rapid and
sensitive, allowing the detection of a wide range of HHV-6 loads. In conclusion, this
test may be useful as a practical tool to help elucidate the clinical relevance of
HHV-6 infection and reactivation in different scenarios and to determine the need for
surveillance. 相似文献
62.
Compartment‐specific aggregases direct distinct nuclear and cytoplasmic aggregate deposition
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Annett Neuner Mohamed YH Mohamed D Lys Guilbride Karsten Richter Michael Lisby Elmar Schiebel Axel Mogk Bernd Bukau 《The EMBO journal》2015,34(6):778-797
Disruption of the functional protein balance in living cells activates protective quality control systems to repair damaged proteins or sequester potentially cytotoxic misfolded proteins into aggregates. The established model based on Saccharomyces cerevisiae indicates that aggregating proteins in the cytosol of eukaryotic cells partition between cytosolic juxtanuclear (JUNQ) and peripheral deposits. Substrate ubiquitination acts as the sorting principle determining JUNQ deposition and subsequent degradation. Here, we show that JUNQ unexpectedly resides inside the nucleus, defining a new intranuclear quality control compartment, INQ, for the deposition of both nuclear and cytosolic misfolded proteins, irrespective of ubiquitination. Deposition of misfolded cytosolic proteins at INQ involves chaperone‐assisted nuclear import via nuclear pores. The compartment‐specific aggregases, Btn2 (nuclear) and Hsp42 (cytosolic), direct protein deposition to nuclear INQ and cytosolic (CytoQ) sites, respectively. Intriguingly, Btn2 is transiently induced by both protein folding stress and DNA replication stress, with DNA surveillance proteins accumulating at INQ. Our data therefore reveal a bipartite, inter‐compartmental protein quality control system linked to DNA surveillance via INQ and Btn2. 相似文献
63.
Abscisic acid (ABA) is a key regulator of plant growth and development, as well as plant defense responses. A high-throughput in planta proteome screen identified the pepper (Capsicum annuum) GRAM (for glucosyltransferases, Rab-like GTPase activators, and myotubularins) domain-containing ABA-RESPONSIVE1 (ABR1), which is highly induced by infection with avirulent Xanthomonas campestris pv vesicatoria and also by treatment with ABA. The GRAM domain is essential for the cell death response and for the nuclear localization of ABR1. ABR1 is required for priming cell death and reactive oxygen species production, as well as ABA-salicylic acid (SA) antagonism. Silencing of ABR1 significantly compromised the hypersensitive response but enhanced bacterial pathogen growth and ABA levels in pepper. High levels of ABA in ABR1-silenced plants antagonized the SA levels induced by pathogen infection. Heterologous transgenic expression of ABR1 in Arabidopsis thaliana conferred enhanced resistance to Pseudomonas syringae pv tomato and Hyaloperonospora arabidopsidis infection. The susceptibility of the Arabidopsis ABR1 putative ortholog mutant, abr1, to these pathogens also supports the involvement of ABR1 in disease resistance. Together, these results reveal ABR1 as a novel negative regulator of ABA signaling and suggest that the nuclear ABR1 pool is essential for the cell death induction associated with ABA-SA antagonism. 相似文献
64.
Kim MJ Kim CS Park JY Park SN Yoo SY Lee SY Kook JK 《Journal of microbiology (Seoul, Korea)》2011,49(1):165-168
In general, an antimicrobial test for screening anti-caries natural extracts was performed by measuring the minimum bactericidal
concentration (MBC) against the type strains of mutans streptococci. However, it is unclear if the antimicrobial efficiency
of natural extracts on the type strains of mutans streptococci is the same on the clinical strains. In this study, we introduced
a bacterial model system for the screening of anti-caries and determining the optimal concentration of them to develop oral
hygiene products for Korean populations. 相似文献
65.
A previous study reported the cloning of a putative Prevotella nigrescens-specific DNA probe, Pn23, using random shotgun method. The present study evaluated the species-specificity of Pn23 for P. nigrescens using the clinical strains of Prevotella intermedia and P. nigrescens to develop P. nigrescens-specific polymerase chain reaction (PCR) primers. Southern blot analysis showed that the DNA probe, Pn23, detected only the genomic DNA of P. nigrescens strains. PCR showed that the two sets of PCR primers, Pn23-F1/Pn23-R1 and Pn23-F2/Pn23-R2, had species-specificity for P. nigrescens. Interestingly, the two sets of PCR primers, Pn23-F6/Pn23-R6 and Pn23-F7/Pn23-R7, had strain-specificity for P. nigrescens ATCC 33563. The detection limits of the four primer sets were 40 or 4 pg of the purified genomic DNA of P. nigrescens ATCC 33563. These results suggest that the DNA probe, Pn23, and the two sets of PCR primers, Pn23-F1/Pn23-R1 and Pn23-F2/Pn23-R2, can be useful for the detection of P. nigrescens in the molecular epidemiological studies of oral infectious diseases. 相似文献
66.
Background
Adult Clonorchis sinensis live in the bile duct and cause clonorchiasis. It is known that the C. sinensis metacercariae excyst in the duodenum and migrate up to the bile duct through the common bile duct. However, no direct evidence is available on the in vivo migration of newly excysted C. sinensis juveniles (CsNEJs). Advanced imaging technologies now allow the in vivo migration and localization to be visualized. In the present study, we sought to determine how sensitively CsNEJs respond to bile and how fast they migrate to the intrahepatic bile duct using PET-CT.Methodology/Principal Findings
CsNEJs were radiolabeled with 18F-fluorodeoxyglucose (18F-FDG). Rabbits with a gallbladder contraction response to cholecystokinin-8 (CCK-8) injection were pre-screened using cholescintigraphy. In these rabbits, gallbladders contracted by 50% in volume at an average of 11.5 min post-injection. The four rabbits examined were kept anesthetized and a catheter inserted into the mid duodenum. Gallbladder contraction was stimulated by injecting CCK-8 (20 ng/kg every minute) over the experiment. Anatomical images were acquired by CT initially and dynamic PET was then carried out for 90 min with a 3-min acquisition per frame. Twelve minutes after CCK-8 injection, about 3,000 18F-FDG-labeled CsNEJs were inoculated into the mid duodenum through the catheter. Photon signals were detected in the liver 7–9 min after CsNEJs inoculation, and these then increased in the whole liver with stronger intensity in the central area, presenting that the CsNEJs were arriving at the intrahepatic bile ducts.Conclusion
In the duodenum, CsNEJs immediately sense bile and migrate quickly with bile-chemotaxis to reach the intrahepatic bile ducts by way of the ampulla of Vater. 相似文献67.
Yoo SY Kim KJ Lim SH Kim KW Hwang HK Min BM Choe SJ Kook JK 《FEMS microbiology letters》2005,249(2):323-326
In this study, we isolated four bacterial strains grown on mitis-salivarius sucrose bacitracin agar. The strains had similar biochemical characteristics to biotypes I or II of mutans streptococci. The four isolates were identified as Streptococcus downei by 16S rDNA and dextranase gene (dex) sequencing as well as polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) targeting dex. To our knowledge, this is the first report of the isolation and identification of S. downei from dental plaque in humans. The results suggest that S. downei can inhabit the human oral cavity. 相似文献
68.
Guk SM Kook J Jeon YH Choi JH Han ET Shin EH Chai JY 《The Journal of parasitology》2005,91(2):467-470
Mechanisms of host immunosuppression after infection with Toxoplasma gondii are unclear. This study was performed to observe cytokine and immunoglobulin secretions by murine splenic lymphocytes infected in vitro with live, nonreplicating (irradiated) RH tachyzoites on stimulation with concanavalin A (Con A) or lipopolysaccharide (LPS). For lymphocyte cultivation, 3 groups were prepared: coculture with live nonirradiated tachyzoites separated by a transwell (group T), live irradiated tachyzoites without a transwell (group R), and no tachyzoites (group C). Compared with group T, groups R and C, on stimulation with Con A, revealed significantly (P < 0.05) lower levels of interleukin-2 (IL-2) and IFN-gamma, but not IL-10. The levels of IgG1, IgG2a, IgG2b, IgG3, IgA, and IgM were also significantly (P < 0.05) lower in groups R and C than in group T after stimulation with LPS. The results suggest that intracellular infection of murine splenic lymphocytes with T. gondii tachyzoites could impair their capacity to produce cytokine and immunoglobulin secretions. 相似文献
69.
Kim H Kim SH Ying YH Kim HJ Koh YH Kim CJ Lee SH Cha CY Kook YH Kim BJ 《Systematic and applied microbiology》2005,28(5):398-404
In a previous phylogenetic study of the genus Streptomyces using the rpoB gene, N531, which stands for an aspargine residue in position 531 of RpoB instead of serine (S531), known to be associated with natural rifampin resistance in several organisms, was also observed in the RpoB of several Streptomyces species. To determine whether N531 is associated with the rifampin resistance of Streptomyces strains, we analyzed the rifampin minimum inhibitory concentrations (MICs) of 11 strains of the N531 RpoB type (putative rifampin resistant strains) and of 12 strains of the S531 RpoB type. (putative rifampin susceptible strains). In general, the N531 RpoB types showed higher MIC levels (16-128 microg/ml) than the S531 RpoB types (0-8 microg/ml). To determine the isolation frequencies of N531 RpoB types versus rifampin concentration, we applied screening methods involving different rifampin concentrations (0, 20 and 100 microg/ml) to Korean soils. Higher isolation frequencies of the N531 RpoB types were observed at the higher rifampin concentrations. In addition, during the course of this study we developed an allele specific PCR method to detect rifampin resistant Streptomyces strains. Our results strongly suggested that N531 might be involved in a major mechanism of natural rifampin resistance in strains of the genus Streptomyces. 相似文献
70.
Lee SM Yoo SY Kim HS Kim KW Yoon YJ Lim SH Shin HY Kook JK 《Journal of microbiology (Seoul, Korea)》2005,43(3):260-265
The objective of this study was to detect and compare the presence of periodontopathogens in the subgingival plaques of gingivitis lesions in adults who wore fixed orthodontic appliances, as opposed to adults who did not wear any orthodontic appliances. Thirty-six individuals participated in this study. Nineteen of these subjects did not wear any orthodontic appliances, and these subjects comprised the control group. The other 17 individuals had been wearing fixed orthodontic appliances for at least 3 months each. After a periodontal examination, we collected subgingival plaque samples from the gingivitis lesions of each patient. Using PCR based on 16S rDNA, we detected the presence of 6 putative periodontopathogenic species, Treponema denticola, Porphyromonas gingivalis, Tannerella forsythia (formerly Bacteroides forsythus), Prevotella nigrescens, Prevotella intermedia, and Actinobacillus actinomycetemcomitans. With regard to the presence of individual periodontopathogens, we found that T. forsythia, T. denticola, and P. nigrescens were significantly more common in the samples obtained from the orthodontic patients than in the samples obtained from the non-orthodontic patient controls. Our results indicate that the local changes associated with the wearing of fixed orthodontic appliances may affect the prevalence of periodontopathogens in subgingival dental plaques. 相似文献